U.S. Pat. No. 4,940,503 discloses a method wherein abrasion-resistant particles are optionally sprinkled onto an overlay impregnated with a melamine resin or a decorative paper impregnated with melamine resin. Overlay and decorative paper are subsequently pressed together such that a decorative paper with an abrasion-resistant surface results. However, the abrasion resistance that can be accomplished by means of such a method is relatively small compared with other methods.
WO 00/44576 A1 discloses another method wherein abrasion-resistant particles are sprinkled onto the impregnated decorative paper like corundum. Then, fibers are applied together with resin and the system of layers is pressed. The abrasion resistance is also small in this method.
WO 00/44984 A1 discloses a method wherein a special dispersion containing abrasion-resistant particles such as corundum or silicon carbide is sprayed onto a decorative paper. The decorative paper in turn is used in the production of a laminated flooring panel. Though high abrasion values can be attained by means of this method, a great instrumentation expenditure must disadvantageously be made because excess dispersion has to be handled, apparatuses for the directed spraying are necessary, a continuous mixing of the dispersion must be ensured and finally, a great effort for drying must be made.